The Patriots will reconvene for the start of offseason workouts April 20. (Oliver Thomas)

The New England Patriots will return to Gillette Stadium on April 20, when the voluntary offseason workout program officially gets underway.

The program, dispersed over nine weeks and three phases heading into Patriots mandatory veteran minicamp on June 16 through 18, starts lightly. But soon, it will be full speed ahead for reigning Super Bowl champions.

In accordance with the NFL’s collective bargaining agreement, the first wave is two weeks of strength and conditioning workouts along with rehabilitation. The second phase is three weeks of on-field workouts with individual player instruction, as well as drills and team practice without contact or offense against defense. And lastly, the third phase is four weeks, and it affords the team the opportunity to hold 10 non-contact organized team activities with offense going against defense for the first time.

New England’s OTA sessions are scheduled for May 26, May 28-29, June 1, June 3, June 4, June 8, June 9, June 11 and June 12. From there, mandatory minicamp is slated for June 16 through June 18, before the players and coaching staff go their separate ways until training camp in late July.